The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 15, 1998
Filed:
Sep. 13, 1995
Masato Yamada, Gunma-ken, JP;
Makoto Kawasaki, Gunma-ken, JP;
Shin-Etsu Handotai Co., Ltd, Tokyo, JP;
Abstract
A light emitting device with higher luminance than that of a conventional light emitting device is provided. According to the present invention, a light emitting device comprises owing three layers of: a first cladding layer made of a p-type mixed crystal compound semiconductor; a p-type active layer made of a p-type mixed crystal compound semiconductor which has the mixed crystal ratio required to emit the light having a predetermined wavelength; and a second cladding layer made of a mixed crystal compound semiconductor, the conductivity type of which is n throughout the second cladding layer or except the region in the vicinity of the heterojunction with the p-type active layer, wherein the p-type active layer is sandwiched by the first cladding layer and the second cladding layer, and forms the double hetrojunction structure with said both cladding layers, and is characterized in that: the second cladding layer is doped with an n-type impurity or impurities and a p-type impurity or impurities; the total concentration of a p-type impurity or impurities in the second cladding layer is in the range of 1.times.10.sup.17 cm.sup.-3 and more; and a pn junction is formed in the second cladding layer of a position within 1 .mu.m from the heterojunction with the p-type active layer.